In recent years, substrates of semiconductor wafers have been enlarged in diameter from 200 mm type to 300 mm type, and are set to predetermined processing equipment or shipped from the factory while they remain stored in a dedicated substrate storage container. A substrate storage container of this type, includes: as partially shown in FIG. 18, a front open box type container body for storing substrates of semiconductor wafers in alignment; a door element that is removably fitted to the open front portion of the container body; and an elastic gasket that seals between the container body and the door element by deformation, and is designed to be large-sized for increase in diameter of substrates (see Patent document 1).
The container body of the substrate storage container is injection molded of a molding material with a predetermined thickness so as to obtain a certain strength, and a plurality of teeth that horizontally support substrates are arranged in parallel, on both interior sides, in other words, or on the interior surface of both side walls. On either side of the bottom a bottom rail that is contiguous to the rim of the open front portion is integrally formed by the interposition of a thick reinforcing rib for providing rigidity. This container body includes a mount rib for a robotic flange integrally formed on its top, engaging ribs for the door element formed on both sides along the rim of the open front portion, and attachment ribs for control handles integrally formed on the exterior wall surface on both sides.
The door element is formed in such a shape as to fit to the open front portion of the container body, and is formed on both sides with a pair of engaging pieces that each are pivotally supported to engage the engaging ribs on the container body. The gasket is formed of elastomer materials and is comprised of a frame-shaped base that is fitted to the periphery of the door element and a flexible sealing part that is extended from this base and tapered outwards, and deforms by compression between the sealing surface of the open front portion of the container body and the door element.
Patent Document 1:
    Japanese Patent Application Laid-open 2002-68364